SHORT COMMUNICATION

TAPROBANICA, ISSN 1800–427X. June, 2014. Vol. 06, No. 01: pp. 66–67. © Research Center for Climate Change, University of Indonesia, Depok, Indonesia & Taprobanica Private Limited, Homagama, Sri Lanka http://www.sljol.info/index.php/tapro

On the nectar feeding by the fulvous these to fruit- and flower-bearing trees fruit (Rousettus leschenaulti) kilometers away and, while foraging; R. leschenaulti may share the patchily distributed Phytophagous or fruit bats feed primarily on bountiful tree with other fruit bat . There fruits, seeds, and flower buds. Some fruit bats is some evidence that resource partitioning may also feed on flower nectar, a habit that affects occur via the heights at which the different pollination and plant dispersal. As a species exploit fruits and flowers in a given tree consequence of chiropteran nectarivory many (Yapa & Ratnavira, 2013). In the course of commercially important plant species are obtaining nectar from different flowers, these known to be pollinated (Krishnan, 2001). bats will be in contact with pollen. These Nectar is an important source of carbohydrates results in the rubbing of pollen on the faces of and water for bats (Ruby et al., 2000). Plant bats and, during the course of a night’s characteristics that influence pollination include foraging, an individual bat will visit several time of anthesis; mode of nectar secretion; the flowers in perhaps several trees of the same colour, odour, morphology, position of flowers; species transferring pollen from the anther to the amount and protein content of pollen; the the stigma, the basis of chiropterophily. volume of nectar; and, the concentration of Fulvous fruit bats feed upon many kinds of sugar (Faegri & van der Pijl, 1979). flowers and fruits notably guava (Psydium guajava), soursop (Annona sp.), silk cotton Thirty species of bat have been recorded in Sri (Bombax sp.) and banana (Musa x paradisiaca) Lanka of which four, Rousettus leschenaulti, (Phillips, 1980). Many species of fruit tree giganteus, sphinx, and C. depend on bats to pollinate flowers and the brachyotis, all belonging to the sub-Order colour, size, odour, and shape of these flowers Yinpterochiroptera and Family Pteropodidae, encourage bats to visit. For example, the bracts are almost exclusively frugivorous and covering the inflorescences of banana begin to nectarivorous although a few insects or even open about 30 minutes after sunset and a vertebrates may be ingested by foraging number of creamy white flowers emerge that (Yapa & Ratnavira, 2013). Rousettus last just one night. Maximum exploitation of leschenaulti or the fulvous fruit bat has an banana flowers was around 20:00 h which was altitudinal range extending from sea level to the time of maximum nectar production and 1500m (Phillips, 1980). Its diurnal roosts are sugar concentration in the flowers (Elangovan located in caves, deserted buildings, disused et al., 2000). tunnels and occasionally, trees. R. leschenaulti is exceptional in that it is the only known fruit Our observations were made on 10 December, bat in the world with echolocation ability albeit 2009 commencing at 20:14 h in a suburban a very simple system. The ultrasound becomes garden at Kesbewa, Colombo District, Sri useful in finding their way within their dark Lanka where there was a small clump of banana cave or tunnel roosts (Yapa & Ratnavira, 2013). plants. The observation site was at an elevation Generally, It lives in colonies which may of 38m a.s.l. located in the Wet Zone of the number from as little as 2–3 individuals up to country approximately 21km from Colombo. several thousand (Bates & Harrison, 1997). The night was cloudy and the temperature 25ºC. The diet of R. leschenaulti in Sri Lanka consists of fruit juices, pulp, flower nectar, and leaves We observed a fulvous fruit bat flying around a (Phillips, 1980). A fine sense of smell guides small cluster of banana plants at the observation site. The banana plant had a height of about 3m

66 TAPROBANICA VOL. 06: NO. 01 ON THE NECTAR FEEDING BY THE FULVOUS FRUIT BAT (Rousettus leschenaulti) and carried an unopened inflorescence. This feeding prior to bract opening in order to inflorescence was 30cm in length and 28cm in counter resource competition. width. The single bat made several circling flights around the banana plant and then Literature cited approached the inflorescence before turning Bates, P. J. J. and D. L. Harrison, 1997. Bats of back. It then returned within seconds and flew the Indian Subcontinent. Harrison Zoological close to the inflorescence a few times at heights Museum publication, Kent, UK: 258. between 2–2.8m from ground level. Soon after, the bat landed on the cone of inflorescence Elangovan, V., G. Marimuthu, and T. H. Kunz, although the bract had not yet opened. The bat 2000. Nectar feeding behavior in the short-nosed then briefly looked around while wiggling its fruit bat Cynopterus sphinx (Pteropodidae). Acta ears presumably to determine if the coast was Chiropterologica, 2: 1–5. clear, then started to open the bract of the Faegri, K. and L. van der Pijl, 1979. The banana inflorescence using its muzzle. Opening rd the bract took 35sec. After opening the bract principles of pollination ecology. 3 edition. Pergamon Press, Oxford: 244. the bat immediately crawled toward the flowers, put its rostrum into them, and lapped Krishnan, R., 2001. Observations on food and nectar for nearly 25 seconds (Fig. 1). Then it roosting habits of Indian short-nosed fruit bat looked around again for 12 seconds, all the Cynopterus sphinx (Vahl) (Chiroptera: while wiggling its ears, presumably to check for Pteropodidae) at the I.I.Sc. Campus, Bangalore. safety. After that the bat continued to lap nectar Zoos’ print journal, 16: 592–593. for another 20sec. Finally, it flew away. Phillips, W. W. A., 1980. Manual of the of Sri Lanka - part II (2nd revised edition). Wildlife and Nature Protection Society of Sri Lanka: 267.

Ruby, J., P. T. Nathan, J. Balasingh and T. H. Kunz, 2000. Chemical composition of fruits and leaves eaten by the Short-nosed fruit bat, Cynopterus sphinx (Chiroptera: Pteropodidae). Journal of Chemical Ecology, 26: 2825–2841.

Yapa, A. and G. Ratnavira, 2013. The Mammals of Sri Lanka. Department of Zoology, University of Colombo, Sri Lanka: 364–365.

Submitted: 30 Sept. 2013, Accepted: 23 April 2014 Section Editor: Asoka Yapa

W. G. M. Edirisinghe1 & 2 T. G. T. Kusuminda

1 Wild Rescue Team of Sri Lanka, 183/6 Horana Figure 1: Nectar lapping behavior after the opening Road, Kesbewa, Piliyandala, Sri Lanka Email: [email protected] of Banana bract.

2 Department of Export Agriculture, Faculty of There is no published record we know of forced Agricultural Sciences, Sabaragamuwa University of bract opening of banana inflorescences by Sri Lanka, Belihul-oya, Sri Lanka fulvous fruit bats. Elangovan et al. (2000) Email: [email protected] stated that the animals wait until the bracts open naturally in order to commence feeding. We speculate that R. leschenaulti starts ‘force’

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